Optimum controller design for a spray drying process

Spray dryers represent an important unit operation in industries such as pharmaceuticals and food. Here, a spray drying process that produces micro-particles is used to investigate controller design in two approaches. The first approach assumes the process design is complete and then applies optimal control theory to synthesize the controller. The second approach assumes that both the process and controller designs are to be found together and uses a hierarchical decision-based approach to arrive at the optimal designs. Results are presented to show the possible coupling between the optimal designs that are overlooked in the serial approach.